As a conjunction, one sense of as is “because”: As she was bored, Sue left the room.As also has an equally common use in the sense “while, when”: As the parade passed by, the crowd cheered and applauded. These two senses sometimes result in ambiguity: As the gates were closed, he walked away. (When? Because?) As … as is standard in both positive and negative constructions: The fleet was as widely scattered then as it had been at the start of the conflict. Foreign service is not as attractive as it once was.So … as is sometimes used in negative constructions (… not so attractive as it once was) and in questions (“What is so rare as a day in June?”). The phrase as far as generally introduces a clause: As far as money is concerned, the council has exhausted all its resources. In some informal speech and writing, as far as is treated as a preposition and followed only by an object: As far as money, the council has exhausted all its resources.As to as a compound preposition has long been standard though occasionally criticized as a vague substitute for about, of, on, or concerning: We were undecided as to our destination.As to sometimes occurs at the beginning of a sentence, where it introduces an element that would otherwise have less emphasis: As to his salary, that too will be reviewed.As to what and as to whether are sometimes considered redundant but have long been standard: an argument as to what department was responsible. See also all, because, farther, like1, so1.

as2

[as] /æs/

noun, plural asses

[as-iz] /ˈæs ɪz/ (Show IPA)

1.

a copper coin and early monetary unit of ancient Rome, originally having a nominal weight of a pound of 12 ounces: discontinued c80 b.c.

c.1200, worn-down form of Old English alswa "quite so" (see also), fully established by c.1400. Equivalent to so; any distinction in use is purely idiomatic. Related to German als "as, than," from Middle High German also. Phrase as well "just as much" is recorded from late 15c.; the phrase also can imply "as well as not," "as well as anything else." Interjection of incredulity as if! (i.e. "as if that really could happen") is attested from 1995, an exact duplication of Latin quasi.

(är'sə-nĭk) Symbol AsA metalloid element most commonly occurring as a gray crystal, but also found as a yellow crystal and in other forms. Arsenic and its compounds are highly poisonous and are used to make insecticides, weed killers, and various alloys. Atomic number 33; atomic weight 74.922; valence 3, 5. Gray arsenic melts at 817°C (at 28 atm pressure), sublimes at 613°C, and has a specific gravity of 5.73. See Periodic Table.